Draw works



May 12, 1942. F. J. YOUNG 2,282,634

DRAWWORKS Fiied March :5, 1941 2 Sheets-Sheet 1 nvsntoa Patented May 12, 1942 DRAW WORKS Forrest J. Young, Los Angeles, Calif., assignor to The National Supply Company, Pittsburgh, Pa., a corporation of Pennsylvania Application March 3, 1941, Serial No. 381,503

7 Claims. 7 (01. 74-217) This invention relates to rotary drawworks of the type employed in the drilling of wells, particularly oil, gas, and similar wells, and is particularly directed to the drive means for driving the drawworks spooling drum.

In the construction of rotary drawworks, a trend toward deeper and deeper drilling is reflected in the requirement for bigger and longer spooling drums for the cable, and with this requirement heavier drumshafts are necessary, together with high capacity multiple width sprockets in order to transmit the torque drive essential for operation. Because of the greater length and diameter of the spooling drums, and because of the limitations imposed upon the drumshaft length, it is desirable to employ a minimum number of drumshait driving sprockets. The increasing of the drum diameter and length does not, however, permit of decrease in' speed of operation. On the contrary, in the rotary drilling of a well, speed of operation is of prime importance where long and heavy strings of tools are handled, as the time required for hoisting the drill pipe out of the hole and lowering it into the hole again must be maintained at a minimum. Therefore an essential of a rotary drawworks is that the power drive to the drumshaft must be capable of high speed as well be driven from 'a sleeve element rotatably,

mounted upon the sleeve orj'ackshaft and having means whereby the sleeve element may be driven at a plurality of speeds.

Another object of this invention is to-provide a three-shaft drawworks wherein the drumshaft may be driven through a horizontal chain drive from a jackshaft atone speed and may also be driven from the jackshaft via the lineshaft at another speed.

Other objects and advantages of this invention it is believed will be apparentfrom the following detailed description of a preferred embodiment thereof as illustrated in the accompanying drawings.

In the drawings:

Figure l is a daigrammatic-front elevation of the drawworks embodyingmyinvention.

Figure 2 is a rear elevation thereof.

Figure 3 is an enlarged fragmental plan diagrammatic in character and partly in horizontal section of the drawworks embodying my invention.

In the preferred embodiment of my invention as illustrated in the accompanying drawings, l and 2 indicate supporting frame or post members upon which the drumshaft 3, lineshaft 4, and jack or drive shaft 5, are rotatably supported in suitable bearings. A spooling drum 6 is mounted upon the drumshaft 3. The spooling drum 5 is of a relatively large diameter in its spooling section and of relatively great length. The spooling drum 5 carries at its opposed ends brake rims 1 upon which suitable braking means (not shown) are generally provided.

The spooling drum carries a hub drive member 8 suitably secured to the drum by means of driving pins 9. A quadruple chain drive sprocket I0 is journaled on the drumshaft 3 and a clutch member II is slidably mounted upon the shaft 3 so as to provide a driving connection between the sprocket Hl and drum 6. The clutch I I is connected to the hub 8 by a slidable spline connection l3 and'is adapted to engage the jaws 12 provided on the sprocket l0. Any suitable manner of clutch-shifting means may be provided for shifting the clutch element ll longitudinally of the shaft 3. q

The jackshaft 5 is provided with a quadruple chain drive sprocket M which is keyed to the shaft 5, and connected by a multiple chain to any suitable source of power, not shown. J0ur naled upon the jackshaft 5 is a sleeve element l5 which is rotatably supported upon spaced roller bearings 16. The sleeve element provides a quadruple chain sprocket I! in position of alignment with the drumshaft drive sprocket l0 and in position of substantial horizontal alignment therewith so that the multiplechains l8 providing the transmission drive element between the sprockets l0 and I! extend substantially horizontally. The sleeve element I5 also is provided with an end clutch ring l9 which is suitably secured to the sleeve i5 as indicated at 20.

A clutch collar 2| is mounted upon a clutch sleeve 22 which clutch sleeve 22 is in turn secured to the jackshaft 5.

The clutch ring I9 is provided with exterior clutch splines 23 and the clutch sleeve 22.is also provided with exterior clutch splines 24. 'The clutch ring 2| is provided with spaced interior clutch splines 25 and 26.

- A limiting collar 21 is mounted upon the clutch sleeve 22 to limit longitudinal movement of the clutch ring 2|.

A clutch shifter ring 23 is provided for operation in conjunction with the shifting lever 23 for shifting the clutch ring 2| into position to engage the interior and exterior splines and provide a means of driving the sleeve l6 directly from the shaft 5. This provides the high speed drive for the drumshaft 3 providing a direct drive from the drive sprocket l4 through the shaft 5, sprocket l1 and chain l3 to the sprocket l0. With the clutch element shifted into engagement, a high speed drive is provided for the spooling drum 6.

Mounted upon, and suitably secured to, the

sleeve element I5 is a double sprocket 30 which is positioned in alignment with a double sprocket 3| journaled on the lineshaft 4. A clutch 32 is provided for releasably connecting the sprocket 3| to the lineshaft 4.

Secured to the jackshaft 5 is a double sprocket 33 which drives, through a chain 34, the double sprocket 35 which is keyed or otherwise suitably secured to the lineshaft 4.

A clutch lever 36 is provided for shifting the clutch shifter ring 3'! with the clutch 32. A link 38 connects the shifter levers 29 and 36. A clutch actuating lever 39 positioned at the drillers position of the drawwork structure is operatively connected through actuating levers 40 and 4| with the clutch shifter lever 36 and provides for the simultaneous operation ofthe clutch shifter levers 23 and 36 so that when the clutch 32 is engaged, the clutch ring 2| is shifted to a position of disengagement and when the clutch ring 2| is shifted to a position ,of engagement, the clutch 32 is shifted out of engagement.

With the clutch ring- 2| shifted out of engagement and with the clutch 32 shifted to a position of engagement to connect th sprocket 3| with the line-shaft 4 and with the clutch ll engaged, there is provided a low speed drive to the spooling drum 6 which has three speed reductions. The drive is from the sprocket l4 through the shaft 5 through the sprocket 33, chain 34, sprocket 35, shaft 4, clutch 32, sprocket 3|, through the chain 42 to the double sprocket 30 and then through the quadruple sprocket I1 and chains l8 to the sprocket l0 on the drumshaft maximum permissible chain speed in high speed drive. The size of this sprocket I in turn imposes a limitation upon the size of the jackshaft sprocket l1, since the ratio of the sprocket size must be such as to produce the desired speed of drive of the drum 6. It is therefore apparent that the sizes of the sprockets l0 and II are determined by a survey of the required characteristics of drive when operating under high speed conditions. It also is found on analysis that with the sprocket diameters thus determined, the maximum torque required to be transmitted in low speed drive likewise through the sprockets l0 and I1 reaches a considerably higher value than that carried by the sprockets 33, 35, or the sprockets 30, 3|. As an example, in the construction as illustrated, if the tension in the chains 34 be assumed as 100 units, then the tension in the chains 42. with the ratio as illustrated, will-be approximately 104 units, while the tension in the chains l3 reaches a magnitude of 138 units. Therefore, the chain drive I! is made heavier, i. e., comprising more widths of chains than either of the other transmission drives.

The multiple width of chains are no worse at higher speeds than fewer widths, but doprovide the capacity for high torque transmission particularly under low speed drive conditions. With the ratios of sprocket sizes and under the conditions as hereinabove assumed, the tension in the chains I8 under conditions of direct drive from the shaft 5, i. e., high speed'operation, is approximately '72 units. As the high speed operation provided with the clutch collar 2| engaged is used more frequently for longer periods than the lower speed drive, the diflerence in chain tension is balanced out by the greater service.

Having fully described my invention, it is to be understood that I do not wish to be limited to the details herein set forth, but my invention is of the full scope of the appended claims.

I claim:

1. In a rotary drawworks, the combination of a unitary supporting structure, a drumshaft, a lineshaft and a jackshaft rotatably mounted on said supporting structure in parallel relation, a spooling drum on the drumshaft, means on the jackshaft whereby it may be driven, a sleeve member rotatably mounted on the jackshaft, chain and sprocket means forming a relatively high capacity driving connection between said sleeve member and the drum, chain and sprocket means forming relatively low capacity driving connections between the jackshaft and the lineshaft, and between the lineshaft and said sleeve member, releasable mean to engage the sleeve member directly with the jackshaft to drive the drum through said high capacity driving connection at one speed, and clutch means associated with said relatively small capacity driving connections for selectively driving the drum through said high capacity driving connections at a slower speed..

2. In a rotary drawworks, the combination of a unitary supporting structure, a drumshaft, a lineshaft and a jackshaft rotatably mounted on said supporting structure in parallel relation, a spooling drum on the drumshaft, means on the jackshaft whereby it may be driven, a sleeve member rotatably mounted on the jackshaft, chain and sprocket means forming a compound drive whereby the jackshaft may drive the drum, said means including a primary speed reducing drive from the jackshaft to the lineshaft, a secondary speed reducing drive from the lineshaft to the sleeve member, and a tertiary speed reducin drive from the sleeve member to the drum, the

relative sizes of the sprockets employed in the primary, secondary and tertiary drives being chosen so that the chain tensions in the primary and secondary drives are approximately equal 7 and substantially less than that of the tertiary drive when the compound drive is in operation, selective means to render said compound drive operable or inoperable as desired, and means adapted to releasably connect said sleeve member in direct driving relation with said jackshaft, whereby the drum may be driven through said tertiary drive at a higher speed than that afforded by said compound drive.

3. In a rotary drawworks, the combination of a unitary supporting structure, a drumshaft, a lineshaft and a jackshaft rotatably mounted on said supporting structure in parallel relation, a spooling drum on the drumshaft, means on the jackshaft whereby it may be driven, a sleeve member rotatably mounted on the jackshaft, chain and sprocket means forming a compound drive whereby the jackshaft may drive the drum, said means including a primary speed reducing drive from the jackshaft to the lineshaft, a secondary speed reducing drive from the lineshaft to the sleeve member, and a tertiary'speed reducing drive from the sleeve member to the drum, the relative sizes of the sprockets employed in the primary, secondary, and tertiary drives being chosen so that the chain tensions in the primary and secondary drives are approximately equal and substantially less than that of the tertiary drive when the compound drive is in operation, clutch means associated with said secondary drive whereby the compound drive may be rendered operable or inoperable as desired, and means adapted to releasably connect said sleeve member in direct driving relation with said jackshaft, whereby the drum may be driven through said tertiary drive at a higher speed than that afforded by said compound drive.

4. In a rotary drawworks, the combination of a unitary supporting frame, a jackshaft rotatably mounted on said supporting frame and having means whereby it may be driven, a sleeve member rotatably mounted on the jackshaft and provided witha driving sprocket fixed thereon, a drumshaft assembly including a drum mounted upon a drumshaft, the drumshaft being rotatably mounted on said supporting frame parallel to the jackshaft and positioned substantially at the same level, a driven sprocket rotatably mounted on the drumshaft in alignment with and adapted to be driven by said driving sprocket, clutch means for releasably connecting the driven sprocket in driving relation with said drumshaft assembly, a lineshaft rotatably mounted on said supporting frame parallel to and substantially above said jackshaft and drumshaft, first speed drive means for rotating the sleeve member relative to said jackshaft including a first pair of sprockets mounted coaxially of the jackshaft aligned and connected respectively with a second pair of sprockets mounted coaxially of the lineshaft, one of said first pair of sprockets being adapted to be driven by said jackshaft and the other being secured to rotate with said sleeve member, the second pair of sprockets being adapted to rotate as a unit, a clutch selectively operable for rendering said first speed drive means operative or inoperative as desired, and releasable means adapted to connect the jackshaft directly to said sleeve member to provide a second speed drive.

5. In a rotary drawworks, the combination of a unitary supporting frame, a jackshaft rotatably mounted on said supporting frame and having means whereby it may be driven, a sleeve member rotatably mounted on the jackshaft and provided with a driving sprocket fixed thereon, a

drumshatt assembly including a spooling drum mounted on a drumshaft, the drumshaft being rotatably mounted on said supportingframe parallel to the jackshaft and positioned substantially at the same level, a driven sprocket rotatably mounted on the drumshaft in alignment with and adapted to be driven by said driving sprocket, clutch means for releasably connecting the driven sprocket in driving relation with said drumshaft assembly, a lineshaft rotatably mounted on said supporting frame parallel to and substantially above said jackshaft and drumshaft, first speed drive means for rotating the sleeve member relative to said jackshaft including a first pair of sprockets mounted coaxially of the jackshaft aligned and connected respectively with a second pair of sprockets mounted coaxially of the lineshaft, one of said first pair of sprockets being secured to said jackshaft and the other being secured on said sleeve, one of said second pair of sprockets being secured on the lineshaft and the other being rotatably mounted on the lineshait, clutch means adapted to releasably connect the latter said sprocket to said lineshaft whereby the first speed drive means may be rendered operable or inoperable as desired, and releasable means adapted to connect the jackshaft directly to said sleeve member to provide a second speed drive.

6. In a rotary drawworks, the combination of a drumshaft assembly including a drum mounted upon a drumshaft, a jackshaft and a lineshaft disposed in parallel relation to said drumshaft, chain and sprocket means whereby the jackshaft may drive the lineshaft, means whereby the lineshaft may drive the drumshaft assembly including a sleeve member rotatably mounted on the jackshaft, chain and sprocket means operatively connecting the lineshaft and said sleeve member, and said sleeve member and said drumshaft assembly, a releasable clutch associated with one of said chain and sprocket means whereby the drive to the sleeve member may be rendered operative or inoperative as desired, and clutch means adapted to form a direct driving connection from the jackshaft to the sleeve member.

"I. In a rotary drawworks, the combination of a shaft, means to drive the shaft, a sleeve member rotatably mounted on the shaft, a first sprocket associated with the shaft and adapted to drive a second sprocket rotatably mounted about an axis remote from the shaft, means including a third sprocket associated with the second sprocket and adapted to drive said sleeve member at one speed, clutch means associated with one of said sprockets to render the drive to the sleeve member operative or inoperative as desired, a drumshaft assembly including a spooling drum mounted on a drumshaft, chain and sprocket means whereby the sleeve member may drive the drumshaft assembly, and releasable clutch means operatively connecting the shaft and the sleeve member whereby the sleeve member may be driven at another speed.

FORREST J. YOUNG. 

